#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
int main()
{
   
    int*p = malloc(10);
    if(p == NULL)
        printf("NULL\n");
    bzero(p,10);
    printf("*p = %d\n", *p);
    
    p = realloc(p, 5);
    *p = 100;

}